Weak spark icm bank 2, fluxuating idle, knock and loss of power at uphill

Question

changed sparkplugs, wires, crankshaft position sensor, mechanic claims low pressure at 1 or 2 cylinders and need engine overhaul.

Answer 1

When there is low compression the ignition spark value is decreased, and that particular cylinder does not contribute. so the result is a misfire condition,Depending on the cause of the low compression, and based on the mileage, If there is cylinder valve problem and the engine is high mileage, and you do just the cylinder head , The top would be good and the bottom , the result would be a engine that burns oil.